Dead space is defined as the range of different input values over which there is no change in output value.
Any instrument that exhibits hysteresis also displays dead space, as marked on Figure. Some instruments that do not suffer from any significant hysteresis can still exhibit a dead space in their output characteristics, however. Backlash in gears is a typical cause of dead space, and results in the sort of instrument output characteristic. Backlash is commonly experienced in gear sets used to convert between translational and rotational motion which is a common technique used to measure translational velocity.